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匹配条件: “J.C Kalita” ,找到相关结果约449441条。
Pallabi Goswami,J.C Kalita
International Research Journal of Pharmacy , 2013,
Abstract: In recent years, there has been an increasing concern in the field of endocrine disruption over the presence of various endocrine disrupting chemicals in Pharmaceuticals and Personal care products (PPCPs). This concern has also been as PPCPs are most widely used and had led to introduction of thousands of new and complex chemicals that enter the environment in large quantities. The effect of the chemicals has not only been restricted to human who are exposed directly to the chemicals or the animals which gets exposed to the chemicals through wide variety of veterinary drugs, but also the aquatic organisms and other form of Wildlife which are non target and indirectly gets exposed to the chemicals through individual human activity. Parabens includes a group of compound of which methylparaben, butylparaben, ethylparaben, propylparaben are most widely used as preservatives in various PPCPs. Recent concern over the use of parabens has been drawn by the scientific community as these chemicals are reported to exert a weak estrogenic activity, with butylparaben showing the most potent activity among methyl-, ethyl- and propyl esters in in vitro recombinant yeast assay and in in vivo uterotrophic assay. Human exposure to butylparaben which occur mainly through inhalation, ingestion, or eye or skin contact, from intake of foods or drugs or use of cosmetics and personal care products where butylparaben is mainly used as a preservative. Effects of butylparaben are studied in various animal model systems like rodents to determine the possible effects in human which showed various effects which include defects in male reproductive system like increase in weight of epididymis, also change in serum testosterone level and a significant increase in uterine weight in ovariectomized and immature rats. Other effects include irritation to the respiratory tract, allergic skin reactions, atrophy of lymphoid tissue in the spleen, thymus, and lymph nodes and multifocal degeneration and necrosis in the liver parenchyma were also observed. The aquatic effects of butylparaben include the feminization of male fish and alteration of the behaviors of either sex at part-per-trillion concentrations. A multitude of other aquatic effects are possible because hormone systems are central to the development, functioning, and reproduction of most organisms.
Pallabi Goswami,J.C Kalita
International Research Journal of Pharmacy , 2012,
Abstract: Butylparaben is a commonly used anti microbial preservative in cosmetics, pharmaceuticals and food. The high rate of human exposure of butylparaben has been of growing concern as it is found to mimic estrogen activity in in vitro and in vivo system. Studies showed that butylparaben exerts reproductive toxicity in experimental animals. Several studies report in vivo estrogenic effect in CD1 and CF1 mice and there are known strain differences in sensitivity to endocrine disruption. In this experiment sensitivity of butylparaben exposure on uterus of ovariectomised C3H albino mice was studied through uterotrophic assay considering 5 different doses of 10 mg/Kg body weight/day, 50 mg/Kg body weight/day, 100 mg/Kg body weight/day, 500 mg/Kg body weight/day, 1000 mg/Kg body weight/day for 7 consecutive days through subcutaneous route of administration. The ovariectomised C3H albino mice were grouped as vehicle control (olive oil), positive control (estradiol) and the above five different doses of Butylparaben. After the short term exposure of 7 days butylparaben is found to exert a dose dependent change in uterine weight of ovariectomised C3H albino mice.
Pallabi Goswami,J.C Kalita
International Research Journal of Pharmacy , 2012,
Abstract: In recent years, many environmental pollutants are found to posses estrogenic properties and thus these compounds are known as xenoestrogen or environmental estrogen. These environmental pollutants are present in wide variety of daily used products of human including variety of pharmaceutical and personal care products, foodstuff and products for children. Butylparaben is used in various cosmetics as a preservative like eye care make up products, sunscreen, facial products and skin anti aging products. Many experimental studies in in vivo and in vitro system have shown that butylparaben shows estrogenic activity. In this experiment the effect of butylparaben on studied the total uterine tissue protein in adult C3H albino mice was was studied by lowry method. Four doses of butylparaben 10 mg/Kg body weight/day, 50 mg/Kg body weight/day, 100 mg/Kg body weight/day and 500 mg/Kg body weight/day was administered for 7 consecutive days through subcutaneous route of administration. In the experiment olive oil was used as vehicle control and 17β estradiol was used as positive control. After 7 days of exposure butylparaben was found to increase total uterine tissue protein in adult C3H albino mice.
Pallabi Goswami,J.C Kalita
International Journal of Research in Ayurveda and Pharmacy , 2013,
Abstract: Exposure to natural and synthetic chemicals in the environment, with potential to interfere with the endocrine system, may elicit a wide range of toxic effects in wild-life and in humans, in particular on the reproductive system and with respect to the induction of cancer. Natural estrogens are a group of compounds that are steroid in nature and are primary female sex hormones. Butylparaben, a widely used preservative in many pharmaceuticals, personal care products and foodstuff is found to be estrogenic in nature and elicit toxic effect in various organs including liver, thyroid, kidney, spleen and reproductive organs. For the experiment two doses of butylparaben of 500 mg/kg body weight/day and 1000 mg/Kg body weight/day was considered. The ovariectomised C3H albino mice were grouped as vehicle control (olive oil), positive control (estradiol) and the above two doses of butylparaben which were administered for seven consecutive days through subcutaneous route of administration. After the short-term exposure of seven consecutive days, butylparaben was found to increase in liver weight of ovariectomised C3H albino mice. Positive control (estradiol) showed a significant increase in liver weight (p<0.01) compared to as vehicle control (olive oil). 500 mg/kg body weight/day and 1000 mg/kg body weight/day group showed a significant increase in liver weight (p<0.01) as compared to vehicle control (olive oil).
A determina??o do boro em plantas pelo método colorimétrico da curcumina
Alcarde, J.C.;
Anais da Escola Superior de Agricultura Luiz de Queiroz , 1969, DOI: 10.1590/S0071-12761969000100004
Abstract: the determination of boron in vegetables by the curcumin colorimetric method is based on the formation of the rosocianin complex in acetic-sulphuric media. in this procedure the reaction takes place in solution at room temperature, needing not to control the temperature at 55 3°c, as with the common method in which the rubrocurcumin complex is formed. an aliquot of the vegetable extract is rendered alkiline by adding a solution of naoh and then dried over a vapor bath. to the residue is added a 0,125% curcumin acetic solution and a (1 + 1) acetic-sulphuric solution. the reaction is completed in 15 minutes. in the application of the method to plant materials analysis, several aspects were studied: interferents and their elimination, the recovery of boron from the ashed samples, the contamination due to filtration through paper filter, and the precision and accuracy of the method. among the normally found elements in vegetable aske, the one interfering were: ca2+, mg2+, fe3+, mn2+ and co2+. they were separated by passing the extract through cation exchange resin. the method, as described, may be considered efficient for the boron determination in vegetables, since it showed good precision and accuracy, coupled with high sensitivity, allowing the determination of as low as 2 ppm of boron in vegetables, within the limits of the least erros.
La revolución de los microarrays en la investigación biosanitaria: tipos de plataformas, usos y perspectivas en oncología
Anales del Sistema Sanitario de Navarra , 2004, DOI: 10.4321/S1137-66272004000100002
Abstract: through the introduction, use and management of genome-based tools, research into genetic alterations that give rise to diseases as common as cancer has undergone a technical revolution comparable to the introduction of the microscope in laboratories. now, study of the gene-disease relationship is no longer based on analysing a single gene and its effects, but on analysing the behaviour of thousands of genes in a simultaneous form. these systems, generically called matrices, arrays, microarrays or biochips, are changing the way we pose problems and draw conclusions from experiments, since they offer us a complex photo of the genome as a whole. analyses of expression through microarrays of cdni or oligos are now accessible to the spanish scientific community. the results have proved fascinating to researchers since they can be reproduced easily and contribute a great quantity of information on the regulation of the gene expression in normal and pathological conditions.
Interacción entre fármacos y plantas medicinales
Anales del Sistema Sanitario de Navarra , 2006, DOI: 10.4321/S1137-66272006000300007
Abstract: in recent years there has been a notable increase in the consumption of medicinal plants in spanish society. this might be due to the fact that in some cases they have shown themselves to be efficient in treating certain pathologies and to the erroneous perception that these products are innocuous. medicinal plants behave as authentic medicines since the chemical substances of which they are formed can have a biological activity in humans. for this reason, their joint administration with "conventional medicines" can produce variations in the magnitude of the effect. this type of interaction, just like those produced between two or more medicines, can produce pharmacokinetic mechanisms if they affect the processes of absorption, distribution, metabolism and excretion, or pharmacodynamic mechanisms if they affect the result of the pharmacological action. in the medical literature there are few articles and notifications of cases concerning the adverse effects and interactions that affect medicinal plants, which probably reflects an under-notification of these phenomena. if we add to this the lack of experimental data and controlled studies, perception of their prevalence is difficult or nearly impossible. this article sets out, in an order that will be explained later, the findings of an exhaustive review of the medical literature with the aim of making its existence known to the reader, without going into other considerations, such as the degree of evidence for example, which will be the subject of forthcoming articles.
Biochemical characterization of the GM2 gangliosidosis B1 variant
Tutor, J.C.;
Brazilian Journal of Medical and Biological Research , 2004, DOI: 10.1590/S0100-879X2004000600001
Abstract: the deficiency of the a isoenzyme of ?-hexosaminidase (hex) produced by different mutations of the gene that codes for the a subunit (tay-sachs disease) has two variants with enzymological differences: the b variant consists of the absence of hex a isoenzyme and the b1 variant produces an inactive hex a isoenzyme for the hydrolysis of the gm2 ganglioside and synthetic substrates with negative charge. in contrast to the early childhood form of the b variant, the b1 variant appears at a later clinical stage (3 to 7 years of age) with neurodegenerative symptoms leading to the death of the patient in the second decade of life. the most frequent mutation responsible for the gm2 gangliosidosis b1 variant is r178h, which has a widespread geographic and ethnic distribution. the highest incidence has been described in portugal, which has been suggested as the point of origin of this mutation. biochemical characterization of this lysosomal disease is carried out using negatively charged synthetic a subunit-specific sulfated substrates, since hex a isoenzyme heat-inactivation assays are not applicable. however, the determination of the apparent activation energy of hex using the neutral substrate 3,3'-dichlorophenolsulfonphthaleinyl n-acetyl-?-d-glucosaminide, may offer a valid alternative. the presence of an a subunit in the a? heterodimer hex a means that its activation energy (41.8 kj/mol) is significantly lower than that of the ?? homodimer hex b (75.1 kj/mol); however, as mutation inactivates the a subunit, the hex a of the b1 variant presents an activation energy that is similar to that of the hex b isoenzyme.
CT&F - Ciencia, Tecnología y Futuro , 1996,
Abstract: biomarker fingerprinting of 20 crude oils from putumayo basin, colombia, shows a vertical segregation of oil families. the lower cretaceous reservoirs (caballos and "u" villeta sands) contain oils that come from a mixture of marine and terrestrial organic matter, deposited in a marginal, "oxic" marine setting. the upper cretaceous ("t" and "n" sands) and tertiary reservoirs contain oils with marine algal input deposited in a reducing, carbonate-rich environment. lithology, environmental conditions and organic matter type of source rocks as predicted from oil biomarker differences correspond to organic composition of two cretaceous source rocks. vertical heterogeneity in the oils, even those from single wells, suggests the presence of two isolated petroleum systems. hydrocarbons from lower cretaceous source rocks charged lower cretaceous reservoirs whereas oils from upper cretaceous source rocks charged upper cretaceous and tertiary reservoirs. oil migration from mature source rocks into multiple reservoirs has been stratigraphically updip along the "regional" sandstone units and vertical migration through faults has been limited. biomarker maturity parameters indicate that all oils were generated from early thermal maturity oil window.
Avalia??o de herbicidas aplicados em pré e pós-emergência na cultura da cebola (Allium cepa L.)
Ferreira, J.C.;
Planta Daninha , 1985, DOI: 10.1590/S0100-83581985000100011
Abstract: two field experiments were carried out in grower's fields of the bebedouro irrigation project, in petrolina, pe, in order to study the performance of several herbicides in controlling weeds on transplanted onion crop and the crop tolerance. the treatments were arranged in a randomized complete block design with 3 replications, in a sandy red -yellow latosol, of low clay and organic matter values. in the experiment i, oxadiazon (1.00 kg/h a), pent imethalin (1.25 kg/h a) and napropamide (1.50 kg/ ha) were applied in pre -emergence, two days aft er transplanting; oxyfluorfen (0.24 and 0.48 kg/h a) in early post emergence, ten days after transplanting; oxadiazon (1.00 kg/ha), oxadiazon (1.00 kg/h a) + ammonium sulphat e (5.00 kg/h a), bentazon (0,72 kg/h a), acifluorfen-sodium (0.32 kg/h a), dinoseb acetate (1.50 kg/h a), setoxydim (0.23 kg/ ha), alloxydim -sodium (1.12kg/ha ), diclofop-methyl (0.72 kg/h a) , and bentazon (0.72 kg/ha) + sethoxydim (0.23 kg/h a), 14 days after transplanting. in the experiment ii, oxadiazon (1.00 kg/h a), oxyfluorfen (0.48 and 0.96 kg/h a), and napropamide (1.50 and 3,00 kg/h a) were applied two days after transplanting; oxyf luorfen (0.48 and 0.96 kg/h a), bentazon (0.72 and 1.44 kg/h a), acifluorfen-sodium (0.27 and 0.54 kg/h a), dinoseb acetate (1.50 and 3.00 kg/h a), and bentazon (0.72 kg/h a) + sethoxydim (0.23 kg/h a), 14 days after transplanting. in evaluations made 20 and 34 days after transplanting, respectively in the experiment i and ii, high levels of weed control by oxadiazon and oxyflurfen herbicides were observed. among other treat ments, acifluorfen -sodium was outs tanding in controlling broad leave weeds and sethoxydin, alloxydim-sodium, napropamide, pendimethalin and bentazon + sethoxydim mixture in grass control. in experiment ii, dinoseb and mainly napropamide affected the develop ment of the onion crop and caused yield reductions.

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